Swimming Pool Heater Reviews
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This page is a swimming pool heater review and buyers guide written by an industry expert to help you pick the best pool heater for your swimming pool. This information includes models of pool heaters from Hayward, Pentair, Raypak, Rheem, Jandy and Zodiac - or you can also read the electric heat pump reviews page. If you are looking for information on solar heating then read this article on how to install a pool solar heater. If you are here shopping for a new pool heater but are still unsure which size you should be looking at then you should read this article that teaches you what size of pool heater do I need?
As the most expensive piece of equipment on the average pool pad choosing the correct heater for your pool is an important decision. In addition to being expensive the heater is one of the easiest components to damage from improper installation or chemical damage. An average life expectancy for a pool heater is from 7-10 years however it is not uncommon to see heaters fail in less than 3 years. When this happens to you as a pool owner there is a strong inclination to blame the manufacturer for producing a defective product. While the potential for a defective product is always a possibility the reality is that chemical damage and improper installation is more common than you might realize.
As an experienced pool technician but also having experience working as technical support for a large pool equipment manufacturer I have reviewed hundreds of failed heaters. In many cases no warranty support was provided due to evidence of chemical damage associated with pH and chlorine imbalance as well as poor installation practices. As a pool owner with a failed heater it is only natural to seek to assign blame that might result in free replacement however the review process used for evaluating heater failure is usually very conclusive. Seeing hundreds of failed heaters you see the same distinct failures time and again. Avoiding these main areas of pool heater failure are sure to increase the lifetime you can expect to get from a new heater installation.
Common Causes For Heater Failure You Must Avoid
Chemical damage and galvanic corrosion are the main causes of premature heater failure. In the most extreme of cases heaters can be corroded beyond repair in as
little as 6 months after installation. If this happens to you the manufacturer will request pictures of the heater installation prior to removing the defective unit.
They may also send a gas service technician to your house to review and inspect the installation as well as some of the heater internals looking for evidence of
improper care. There are a lot of things that can void a heater warranty but the most commonly encountered deficiencies that you can avoid are:
- Be sure that the casing of the heater is electrically bonded
- Salt water chlorine generator is installed after the heater
- Check valve is installed between the chlorine generator (or erosion feeder) and the heater to prevent backflow
- Chlorine, pH and calcium hardness must be balanced at all times
The real frustration for pool owners comes from thinking that they have paid a professional to install a heater only to find that their heater has failed from one of these reasons and the manufacturer is refusing warranty. The problem is that not every pool guy knows this information about what can make a heater fail or what will cause a manufacturer to refuse warranty coverage. The area that I work in has the largest concentration of inground pools in the Country and still 8 out of 10 heater installations I see have at least one of the deficiencies listed above. As the pool owner and the one responsible for paying for the pool equipment and maintenance you need to educate yourself and verify that your heater is installed properly.
Bonding The Case Of The Heater
One of the most primary defenses your heater has against galvanic corrosion is the bonding wire attached to the casing of the heater. This is the most common
deficiency to find in heaters that have failed prematurely and one of the most simple problems to rectify. You should inspect your heater to make sure that you can
locate the bonding lug and make sure it is not empty as shown in the pictures below. To bond the heater a thick copper ground wire, commonly #6 AWG bare copper, is
connected to this lug on the casing and the other end connects to the main electrical ground for your house electrical service. Alternatively you can install a
grounding plate near to the pool equipment and run the ground wire to there if the main panel is not accessible. This work is usually performed by licensed
By providing a low resistance path to ground via the bonding wire this will prevent small voltages from developing between the heater and other components of your pool which are electrically "connected" via electrolytes, or salt, in the water. Even if you do not have a salt water pool you still have salt in your pool as sodium is the base compound for chlorine. Salt water pools have salt levels around six times higher than traditional chlorine pools so heaters that are not bonded on salt water pools will fail even faster.
Where To Install A Salt Cell In Relation To The Heater
Pool equipment needs to be installed in a specific order which is pump, filter, heater and then the salt water chlorinator generation cell. If you install a salt cell
anywhere before the heater then you are sending concentrated chlorine directly through the most expensive and most chlorine sensitive piece of equipment on your pool.
The damage from concentrated chlorine will absolutely ruin the heater even after only a few weeks following installation. The heater contains many metal components
which can not survive heavy doses of chlorine and that is why the salt chlorinator cell is installed directly after the heater. This allows only fully diluted water
from the pool to reach the internals of the heater. It is for this same reason that it is strongly not recommended to put chlorine pucks into your skimmer strainer
basket or your pump strainer basket.
A corrosion resistant check valve is needed in between the salt cell and the heater
Installing the salt cell after the heater is not even enough to protect the heater from the corrosive chlorine since it is possible under normal operation for chlorine to track backwards through the system and access the heater. This is especially true for any time a pump turns off on a salt water pool as the chlorine continues to generate for a few moments. If possible this chlorine will travel backwards through the plumbing and become trapped in the heater headers. A salt water cell installed after the heater with no check valve in place to isolate it will absolutely fail earlier than a similar heater installation with a check valve.
The same is true for any source of chlorine feed in your pool system. If you have a regular erosion feeder that holds chlorine pucks it must be installed after the heater in the plumbing configuration. Additionally you should install a corrosion resistant check valve on the line out of your heater. Just as with a salt chlorination cell an erosion feeder can allow concentrated chlorine to travel backwards through the heater causing an premature failure of the internal metal components. Even if the salt cell or erosion feeder are downhill this is not good enough as the chlorine can and will travel uphill against gravity every time the system turns off.
Water Chemistry Problems Relating To Heater Failure
This is a very difficult subject as "balanced" chemistry in pool water means different things to different people. The reality is that most pool owners do not really
understand exactly what each chemical does in the water and how the different levels interact with each other. Also, many pool professionals have only just a
rudimentary understanding of water balancing leading to poorly educated end users. Throw in a liberal dose of "I've been doing it this was for 30 years and I never
have a problem" and this pretty much sums up the public approach to balancing pool and spa water.
Even pool owners who legitimately feel they have balancing under control it is unlikely they can explain much about phosphates, breakpoint chlorination, saturation index or galvanic corrosion which is not a knock against them but more an indication of how deep the rabbit hole goes in the world of water chemistry. Short periods of time with very poor water quality or extended periods of time with marginal water quality is enough to cause damage to pool heaters. Of primary importance are:
Maintain pH between 7.2 and 7.8
Any time your pH is outside of this range then damage is likely happening to your heater. A pH of 7 is ten times more acidic than a pH of 8. A pH of 6 is 100 times more acidic than a pH of 8 so you can see why even short periods of imbalance can expose metals to harsh conditions.
Chlorine levels not to exceed 10ppm
Only during periods of superchlorination or breakpoint chlorination do you need to have chlorine levels up to 10ppm. The rest of the time you should try to maintain levels between 1-3 ppm which is perfect for maintaining clean and safe water without putting undue strain on metal components such as the heater
Calcium hardness levels below 400ppm
Scale formation is of primary concern for protecting pool heaters. The scale itself is very corrosive and will damage metal components it forms on. One of the biggest factors that causes scale formation is high calcium hardness levels. Levels below 400 are a must and levels below 200 are ideal.
How To Correctly Size A Swimming Pool Heater
To calculate the size of heater that you need you will need to know the volume of your pool as well as a few details about what kind of performance that you expect
from it. To start with, a BTU is the amount of energy needed to heat 1 lb of water by 1 degree. Since there are 8.83 lbs of water in 1 gallon you can multiply the
pool volume in gallons by 8.83 then divide by 24 to determine the BTU energy needed to heat your pool by 1 degree in 24 hours.
A 16x32 20,000 gallon pool would be (20,000 x 8.83) / 24 = 7358 BTU per hour to heat this pool by 1 degree in 24 hours
Next determine the difference in temperature between the what the pool water is and what you want it to be. Supposing an average unheated pool temperature of 68 degrees and a desired pool temperature of 82 degrees this is a difference in temperature of 12 degrees. You would then multiply 12 by the first calculation of the hourly BTU requirement.
12 x 7358 = 88,296 BTU per hour to achieve a 12 degree rise in temperature in 24 hours
This general guideline is helpful as a relative understanding for how BTU requirements are calculated however the BTU requirements to maintain pool temperature are a more useful calculation. For this next calculation you need to know that you will require 10 BTU for every square foot of surface area of your pool for EACH degree difference between the pool water temperature and surrounding air temperature.
16x32' pool has a surface area of 512 sf x 10 = 5120 BTU for each degree difference between water temp and air temp
Supposing it is 55 degrees and you want the pool at 80 degrees then this represents a 25 degree differential. Multiply 5120 by 25 to determine the hourly BTU requirement to maintain this temperature. In this case 128,000 BTU. By looking at the worst case scenario such as cold ambient temperatures in the spring and fall you will learn the maximum BTU you will require during periods of heavy load. Once you know the theoretical minimum BTU you need to meet your maximum expectations you need to oversize the heater by 20-25% to account for extreme operating conditions such as heavy cross winds as well as efficiency losses that the heater will experience over time. 128,000 with an additional 25% tolerance is 160,000.
The more that you oversize the heater on your pool the easier it will be for your heater to maintain water temperatures which results in longer lasting internal components. There is a point of diminishing returns for over sizing however it is common practice to upgrade to the next size larger standard size heater above what is calculated that you require. In the above example we needed 160,000 BTU however since heaters are produced in round numbers you would be looking at 175,000 BTU models and more likely 200,000 BTU models which are widely available in any brand.
Gas Heaters For Small Pools & Above Ground Pools
Model: Hayward H100ID1 / H100IDP1
BTU rating: 100,000
Buy from Amazon.com: H100ID1 or H100IDP1
Buy from PoolSuppliesCanada.ca: H100ID1 or H100IDP1
This Hayward 100,000 BTU heater is intended for above ground pools and comes with a 110 volt cord end plug for easy electrical installation. This is an electronic spark heater so there is no standing pilot or associated lower operating efficiency that comes with a standing pilot flame. This heater uses a copper heat exchanger and is 81% efficient - most suitable for pools with up to 450 square feet of surface area. This heater is also ideal for hot tubs and spas.
Model: RayPak PR106AENC / PR106AEPC
BTU rating: 106,000
Buy from InTheSwim.com: PR106AENC or PR106AEPC
Buy from Amazon.com: PR106AENC or PR106AEPC
Buy from PoolSuppliesCanada.ca: PR106AENC or PR106AEPC
The RayPak 106A unit has a copper heat exchanger and polymer headers and comes with a cord end for 110 volt installations however it can be converted to 220 volts. It uses an analog heat control dial and a digital ignition pilot hybrid lighting system that only lights the pilot when there is a call for heat. The size of this heater also makes it a good choice for hot tub applications.
Model: Pentair MasterTemp 125
BTU rating: 125,000
Buy from InTheSwim.com: 461061
Buy from Amazon.com: 461059 or 461061
Buy from PoolSuppliesCanada.ca: 461059
The Pentair MasterTemp 125k BTU gas heater is suitable for small pools, above ground pools and small and medium sized hot tubs. This 125,000 BTU heater operates at 82%. Available for 110 volt and 220 volt electrical installations this is a digital control heater so no standing pilot flame is needed. This heater is best suited for pools up to 15,000 gallons.
Model: RayPak PR156AENC / PR156AEPC
BTU rating: 156,000
Buy from InTheSwim.com: PR156AENC or PR156AEPC
Buy from Amazon: PR156AENC or PR156AEPC
Buy from PoolSuppliesCanada.ca: PR156AENC or PR156AEPC
The RayPak 156A is for use with 120 or 240 volt power sources and comes with an all copper heat exchanger. The 156A is digitally controlled and compatible with most automation control systems for remote operation. At 156,000 BTU's this is the heater of choice for larger above ground pools, swim spas and hot tubs.
Hayward Universal Forced Draft Low NOx Electronic Pool Heaters
This versatile heater is the flagship heater from Hayward and has the ability to position the water and gas connection ports on either side of the unit to accommodate any installation layout. The electrical connections are also
available on either side of the heater. The FD model from Hayward has cupro-nickel corrosion resistant heat exchanger suitable for use with salt water
chlorine pools. This forced draft heater is rated up to 84% efficient and is by far the most popular heater that Hayward offers.
Model: Hayward H150FDN / H150FDP
BTU rating: 150,000
Buy from InTheSwim.com: H150FDN or H150FDP
Buy from Amazon.com: H150FDN or H150FDP
Buy from PoolSuppliesCanada.ca: H150FDN or H150FDP
Model: Hayward H200FDN / H200FDP
BTU rating: 200,000
Buy from InTheSwim.com: H200FDN
Buy from Amazon.com: H200FDN or H200FDP
Buy from PoolSuppliesCanada.ca: H200FDN or H200FDP
Model: Hayward H250FDN / H250FDP
BTU rating: 250,000
Buy from InTheSwim.com: H250FDN or H250FDP
Buy from Amazon.com: H250FDN
Buy from PoolSuppliesCanada.ca: H250FDN or H250FDP
Model: Hayward H300FDN / H300FDP
BTU rating: 300,000
Buy from Amazon.com: H300FDN or H300FDP
Buy from PoolSuppliesCanada.ca: H300FDN or H300FDP
Model: Hayward H350FDN / H350FDP
BTU rating: 350,000
Buy from Amazon.com: H350FDN or H350FDP
Buy from PoolSuppliesCanada.ca: H350FDN or H350FDP
Model: Hayward H400FDN / H400FDP
BTU rating: 400,000
Buy from InTheSwim.com: H400FDN or H400FDP
Buy from Amazon.com: H400FDN or H400FDP
Buy from PoolSuppliesCanada.ca: H400FDN or H400FDP
Pentair MasterTemp Low NOx Digital Pool Heaters
A comparable model to the Hayward Universal heaters the Pentair MasterTemp series has 84% efficiency with copper heat exchangers or 82% efficiency with cupro-nickel
heat exchangers which are more capable of handling more adverse chemical conditions and salt water applications. This is a very compact heater and the entire casing
is comprised of corrosion resistant materials.
Model: Pentair 460730 / 460731
BTU rating: 200,000
Buy from InTheSwim.com: 460731
Buy from Amazon.com: 460730 or 460731
Buy from PoolSuppliesCanada.ca: 460730
Model: Pentair 460732 / 460733
BTU rating: 250,000
Buy from InTheSwim.com: 460733
Buy from Amazon.com: 460732 or 460733
Buy from PoolSuppliesCanada.ca: 460732
Model: Pentair 460734 / 460735
BTU rating: 300,000
Buy from InTheSwim.com: 460735
Buy from Amazon.com: 460734 or 460735
Model: Pentair 460736 / 460737
BTU rating: 400,000
Buy from InTheSwim.com: 460737
Buy from PoolSuppliesCanada.ca: 460736
Sta-Rite Max-E-Therm Digital Pool Heaters
Sta-Rite is an established pool equipment brand that was purchased by Pentair in 2004 so you will see many similarities between the black Sta-Rite brand and the almond
Pentair brand. In many cases the only difference between the Pentair and Sta-Rite versions of products is the color of the casing only. This is the case for the
Max-E-Therm heaters and the Pentair MasterTemp series. The Max-E-Therm also has an 84% efficiency rating with a standard copper heat exchanger and 82% efficiency with
a heavy duty, salt water and corrosion resistant, cupro-nickel heat exchanger. This unit is very compact and is the lightest heater in its class though it is limited
in BTU size selection. All models of this heater are suitable for salt water pools.
Model: Sta-Rite SR200NA / SR200LP
BTU rating: 200,000
Buy from InTheSwim.com: SR200NA or SR200LP
Buy from Amazon.com: SR200NA or SR200LP
Model: Sta-Rite SR333NA / SR333LP
BTU rating: 333,000
Buy from InTheSwim.com: SR333NA or SR333LP
Buy from Amazon.com: SR333NA or SR333LP
Model: Sta-Rite SR400NA
BTU rating: 400,000
Buy from InTheSwim.com: SR400NA or SR400LP
Jandy / Zodiac Digital Pool Heaters
The new JXi series of digital pool heaters from Jandy (Zodiac) are 83% efficient and come with a host of technical upgrades over previous models of heaters from this brand. Most notably this heater has the smallest footprint of any gas pool heater at only 24 inches square. The top of these heaters can rotate 180 degrees to facilitate the most simple universal installation possible. The Versa Flo bypass and Versa Plumb option are something that Jandy has developed to allow for a reduction in flow resistance in the system. This also allows for a total system installation with the smallest possible footprint while managing to increase the efficiency of the flow dynamics of the system. All Jandy JXi heaters are compatible with salt water systems. These heaters will not be available to buy online. They are available from brick and mortar stores only.
Model: Jandy JXi200N / JXi200P
BTU rating: 200,000
Buy from Amazon.com: JXi200N or JXi200P
Buy from PoolSuppliesCanada.ca: JXi200N or JXi200P
Model: Jandy JXi260N / JXi260P
BTU rating: 260,000
Buy from Amazon.com: JXi260N or JXi260P
Buy from PoolSuppliesCanada.ca: JXi260N or JXi260P
Model: Jandy JXi400N / JXi400P
BTU rating: 400,000
Buy from Amazon.com: JXi400N or JXi400P
Buy from PoolSuppliesCanada.ca: JXi400N or JXi400P
Raypak / Rheem Digital Pool Heaters
The Raypak and Rheem brand of pool and spa heaters are similar heaters sold under different badges for competing distribution channels. Other than wind stack
differences they are essentially the exact same heater. The standard units have a copper heat exchanger and operate at 83% efficiency where the cupro-nickel upgraded
corrosion resistant versions have a slightly lower efficiency rating of 81% but are much better suited to longevity against corrosion failure especially with salt water pools.
Model: RayPak PR206AENC / PR206AEPC
BTU rating: 195,500
Buy from InTheSwim.com: PR206AENC or PR206AEPC
Buy from Amazon.com: PR206AENC or PR206AEPC
Buy from PoolSuppliesCanada.ca: PR206AENC or PR206AEPC
Model: RayPak PR266AENC / PR266AEPC
BTU rating: 266,000
Buy from InTheSwim.com: PR266AENC or PR266AEPC
Buy from PoolSuppliesCanada.ca: PR266AENC or PR266AEPC
Model: RayPak PR336AENC / PR336AEPC
BTU rating: 332,500
Buy from InTheSwim.com: PR336AENC
Buy from Amazon.com: PR336AENC or PR336AEPC
Buy from PoolSuppliesCanada.ca: PR336AENC or PR336AEPC
Model: RayPak PR399AENC / PR399AEPC
BTU rating: 399,000
Buy from InTheSwim.com: PR399AENC or PR399AEPC
Buy from Amazon.com: PR399AENC or PR399AEPC
Buy from PoolSuppliesCanada.ca: PR399AENC or PR399AEPC
Model: RayPak PR206AENX / PR206AEPX (Cupro Nickel)
BTU rating: 180,000
Buy from InTheSwim.com: PR206AENX or PR206AEPX
Buy from PoolSuppliesCanada.ca: PR206AENX
Model: RayPak PR266AENX / PR266AEPX (Cupro Nickel)
BTU rating: 240,000
Buy from InTheSwim.com: PR266AENX or PR266AEPX
Buy from PoolSuppliesCanada.ca: PR266AENX
Model: RayPak PR366AENX / PR366AEPX (Cupro Nickel)
BTU rating: 300,000
Buy from InTheSwim.com: PR366AENX or PR366AEPX
Buy from PoolSuppliesCanada.ca: PR366AENX
Model: RayPak PR399AENX / PR399AEPX (Cupro Nickel)
BTU rating: 360,000
Buy from InTheSwim.com: PR366AENX or PR366AEPX
Buy from PoolSuppliesCanada.ca: PR399AENX
How To Choose The Right Heat Exchanger Material
Copper Heat Exchangers
Almost all of the premiere digital controlled gas pool heaters available have different models of heat exchanger options. For most heaters the standard heat exchanger material is copper and these are suitable for any balanced pool and spa environment. The addition of salt water to the system is a concern for copper heat exchangers however with proper water maintenance, electrical bonding and the addition of a sacrificial anode to the pool system, copper heat exchangers can be used with salt water chlorine pools.
Cupro-Nickel Heat Exchangers
Since a heater is a very expensive piece of pool equipment anyone with a salt water pool would be well advised to pay extra to get the heat exchanger model upgraded to cupro-nickel which is more resistant to chemical damage, fluctuating pH and salt water. This upgrade usually costs an additional 10-20% over the cost of the base model copper heat exchanger.
ASME Copper Heat Exchangers
Many of the flagship digital heaters will also have a third heat exchanger option called ASME approved. ASME is the American Society of Mechanical Engineers and heaters bearing the ASME designation have upgraded material thickness of the heat exchanger (and often header) materials. ASME heaters are considered suitable for commercial applications and would be considered overkill for residential applications unless you want the absolute best that money can buy in which case ASME represents the highest possible quality available - and the highest price tag with heaters being as much as 50% more than base model units. For salt water the thicker copper exchanger is better than the basic but the cupro-nickel version is specifically made for this application.
What Is The Best Pool Heater?
Since pool and spa heaters are expensive there are many shoppers who are looking for the cheapest possible heater and are willing to give up creature comforts like digital controls and digital ignition. Also some pool heater installations do not have the possibility to have electrical available which makes millivolt and standing pilot gas heaters a good option.
Millivolt heaters are the lowest cost pool heaters you can buy short of solar heaters but they have the ability to heat your pool just as well as more expensive digital pool heaters. In fact many service technicians prefer the base model, analog, standing pilot heaters as these stripped down units have very little that can go wrong with them. Even when these heaters do fail they tend to have fairly simple and low cost replacement components as opposed to digital heaters that can be prone to electronic failures which are always expensive to fix since you do not troubleshoot to the component level - if a board is malfunctioning you simply replace the board. If you are looking to get your pool warmer with as little upfront investment as possible then a millivolt heater is a low cost, simple to install option.
When you start to ask about what is the best brand of pool heater then you are going to have a hard time getting a clear and honest answer. The reason for this is simple in that every technician, and pool owner for that matter, will have a personal preference for one brand or another. Most of these preferences are based on personal experience, good or bad, but lack overall perspective on the pool heater industry as a whole. When I worked in heater warranty claims and national account sales for swimming pool equipment I had access to a top-down view of the pool industry. Part of the benefit of this is I had access to warranty and failure rates for pool equipment on a national scale and this really puts failure rates for pool equipment in perspective.
What this perspective showed is that every iota of energy you are putting into researching which brand of pool heater is the best would be better spent researching how to install a heater correctly and how to maintain your water chemistry properly. This is not meant to dissuade you from doing your due diligence research on pool heaters, but more to point out that if you go looking for negative reviews about ANY brand of pool heater then you are going to find some. This would not be accurate in any way to reflecting the national averages of pool heater failure rates and tend to actually lead you away from what would otherwise be very popular brands and models of pool heater. In order to help address this important question with a difficult to quantify answer I contacted a number of swimming pool heater experts, gas technicians and high volume retail stores to find out which are the best pool heaters. By asking the people who work with, and install pool heaters on a daily basis, you will likely find better and more proactive information to help you determine which is the best pool heater for you. If you would like to read the responses from these heater experts as to what is the best pool heater you can read their responses which were condensed into this article: What is the best pool heater?.
What Is The Most Common Size Of Pool Heater
In some cases you will notice there is little or no cost difference between different BTU size heaters, and in some cases smaller size heaters can even be slightly more
money that a larger version of the same model. This is due to supply and demand. In the residential market 250,000 BTU gas heaters make up over 70% of the entire
pool heater market. Since the 250k BTU heaters tend to outsell every other size of heater put together there exists the possibility for bulk purchasing of these units
from manufacturers. This can result in savings being passed down to the end user.
If your pool would size well to a 200,000 BTU heater you may want to consider up-sizing to a 250,000 as you may be able to get a better price, and replacement parts will be widely available in the future. One concern for this is gas line sizing as the gas line must be large enough to supply the increase in demand. If you have an existing 200,000 BTU heater then you need to make sure that your gas line is large enough to accommodate the larger model. While 1" gas line may be used for up to 290,000 BTU this does not take into account for reductions due to length of run, elbow and fittings etc. In most cases 1 1/4" pipe will be required for 250,000 BTU heaters to be on the safe side. Not providing enough gas flow can cause heaters to have an incorrect fuel to air ratio resulting in a loss of operating efficiency, soot buildup and the potential for error codes or the heater not functioning.
Learn How To Protect Your Pool Heater
If you are purchasing a new heater for your pool then you should learn as much as possible about how to make it last a long time. More times than not the reason an existing pool heater will fail is from a preventable cause. If you have a pool heater that you want to protect or you are in the process of buying a new pool heater then be sure to review the pool heater checklist to make sure you are doing everything you can to protect your heater from damage.
Improper installation, not protecting your heater from chlorine, or failure to keep your pH in the correct range can all result in early heater failure. The problem is that this failure can happen much sooner than you might expect. Pool heater manufacturers say that seven to ten years is a normal service life for a new pool heater. Obviously you would hope to get even longer if possible, however if you fail to protect your heater from all of these adverse conditions then you may find your heater dead in less than one year!
Some products are designed to be rugged and abused but keep working. Swimming pool heaters are not one of those things. Pool heaters require a carefully calibrated balance of fuel, air and ignition along with specific flow rates and chemical ranges for water. If you start to change any of these variables then the heater begins to operate inefficiently and internal damage can happen very quickly. Consider your pool heater like a piece of high end consumer electronics...that you keep in the backyard...that has a massive fire burning inside it...that you pump chemically treated water through. What could possibly go wrong? If you are still wondering what the best pool heater is and you would like to read more then check out this article where we asked pool heater experts and gas technicians exactly that... What is the best pool heater?
How Long Will A New Pool Heater Last?
If you are about to retire your old pool heater from service after 25+ years of mostly trouble free operation then you are not going to be very impressed with how long your new heater will last for. Most pool equipment manufacturers and heater experts agree that the average pool heater produced today will last for seven years. This figure, alarming as it is, is often not interpreted correctly. While it is true, and accurate, that new pool heaters will have an average service life of seven years, this is taking into consideration both extremes of the spectrum. The most significant extreme is heaters that fail early due to poor installation or chemical maintenance of the pool water which substantially drags down the "average heater life expectancy".
A lack of heater bonding, lack of water flow bypass valves, improper water chemistry maintenance, lack of check valve protecting the heater from downstream chlorine injection systems, lack of regular cleaning and maintenance of the heater, improper gas line sizing, improper vent sizing or inadequate breathing room...any of these problems could, and would, most likely cause a brand new heater to install early. Very early. I have personally encountered a new residential heater that was destroyed beyond repair in under three months. In total I have consulted with hundreds of pool owners with heaters that were destroyed in less than one year. Do not underestimate just how much incorrect installation or chemical maintenance will impact the service life of your new heater...this would be a mistake that ends up costing you money 99 times out of 100.
On the other end of the extreme spectrum is the people who get more than seven years service life out of their heater. This is the real question that pool owners want to know; how long can a new pool heater last?. The average heater life expectancy includes pool owners by the thousands who do not care for their pool or their pool equipment properly. If you are the type of person that takes pride in your swimming pool and pool equipment maintenance then how long would you, specifically, expect your new heater to last? The answer to that will depend most heavily on water chemistry, but on average 10 to 12 years should be no problem at all.
After a correct installation of a new heater, provided that you maintain the pool and service the heater regularly you will most likely get 10 or more years out of your heater. Perhaps a few people will get between 15 to 20 years and a tiny percentage of heater owners who will receive in excess of 25 years of service life. Now, to qualify this statement, regular replacement of integral components may likely be required during this period of time.
All things considered, if you are prepared to do what it takes to protect your investment in a new pool heater then where should you focus your efforts? The answer to this is water chemistry. Most pool owners know that water chemistry is important, and some very informed pool owners know that water chemistry might be the most important thing that impacts the service life of your pool equipment. Aside from just saying to make sure your water chemistry is "good", there is some specific knowledge that can help you to get the most life out of your heater. One of the biggest, most heater-destroying chemical situations you can have with your pool water is to have two specific things at the same time:
1) High Chlorine Levels
2) Low pH Level
If you have the specific water condition where you have a high chlorine level in the water as well as low water pH (acidic water state) then this can be extremely problematic for pool heaters. Of all the chemical conditions that a pool heater is likely to experience, having acidic water conditions below pH 7.0 while also having free chlorine levels in excess of 5 parts per million, the metal plating within the heater will deteriorate. Even a few brief instances of high chlorine combined with low pH can drastically damage internal metal components on your heater. As a new heater owner you should be sure to keep your pool water pH above 7.2 at all times...which is in theory easy enough to do.
In the real world things happen. You could have some kind of equipment failure that causes low pH, or you could make a single mistake with your chemical maintenance and low pH of the water results. This is why it is so important to have your heater installed with a bypass so that any time that you need you can take your heater offline and prevent less than ideal water chemistry from reaching your heater internals. If you want more information about how to properly protect your heater then you can read this follow up article: The Pool Heater Checklist.
Pool Gas Heater VS Electric Heat Pumps
A very common question from pool owners hoping for a new gas heater is actually whether you should be getting a gas heater at all. It is very difficult for the average pool owner to get decent, unbiased advice about pool gas heaters versus electric heat pumps because the answer to your questions about which would be best for you will depend heavily on two criteria:
1) Your Geographic Location
2) Your expectations of heat
Warm climate - If you live in an area where you have sub zero winter temperatures then you will experience less benefit from an electric heat pump versus a geographic area that never really gets cold. The reason for this is an electric heat pump does not operate exactly like a gas heater does. A gas heater is extremely powerful and has far, far more heating ability than an electric heat pump could hope to provide even under ideal conditions. A gas heater works no matter of current air or water temperature...so long as you feed it money, it will make your pool warmer. An electric heat pump is defined by being an economical form of pool heat, but with a huge caveat. Heat pumps are designed for a specific purpose, which is to take ambient warm air and direct sunlight and use this, via a reverse air conditioner-like system, to warm pool water. If you live in an area where it is generally warm and sunny then an electric heat pump might be a very good choice for you. Since an electric heat pump can not operate when ambient air temperature is cool or cold, it will be unable to heat pool water when it is not already hot and sunny.
How much heat you expect - There are two basic ways that you might want to heat a pool which are to extend your swimming season into colder months, or to improve your in-season swimming temperatures. The answer to whether a gas heater or an electric heat pump would be best for you will largely depend on how you expect your heater to operate. In simple terms, an electric heat pump is ideal for improving in-season swimming temperatures in areas where it is typically warm and sunny already. Gas heaters are ideal for providing heat to swimming pools when ambient air temperature and regular water temperatures are not warm enough for swimming normally.
Gas heaters and electric heat pumps actually compliment each other very well in terms of performance and efficiency. In theory, the most advanced and efficient swimming pool systems would include multiple heating sources. This allows you to benefit from the instant heat performance of gas heating, while also benefiting from the maintenance heating effect that electric heat pumps are best suited for. Of course for the average pool owner having both an electric heat pump and a gas heater will be cost prohibitive, but if you are designing a pool with energy efficiency and long term cost effectiveness you should certainly consider systems that use both gas heat as well as a heat pump. If you would like to read more about how heat pumps work and the amount of electrical demand they have (it's a lot) then you can read these heat pump reviews.
What Is The Cheapest Way To Heat A Pool?
As discussed above, the cheapest way to heat your pool will depend on what, and how much, you expect your water to be heated. For example a pool solar heater will provide the cheapest heat for your pool on an ongoing basis, but if your solar heater only heated your water from 72 to 74 degrees, would you be happy with that? Would you consider that a good deal since, technically, it is the cheapest way to heat your pool. Or is this still not good enough? You could dump a few gallons of diesel fuel into your pool and light it on fire directly...the pool might get a little warmer, but that certainly would not make it a good idea, even if it is the cheapest way to heat your pool.
What I am trying to get at is you should not be asking what the cheapest way to heat your pool is. You should identify whether you are looking to increase your in-season swimming temperatures or extend your swimming season into colder months. If you match the type of pool heater you buy to meet your expectations of heat as well as your geographic area and climate then you will already be further ahead then most pool owners.
The problem with "cheap" swimming pool heat is that it does not really exist. What you really should be asking is "what is the best way to heat your pool" and how can you avoid wasting this heat that you paid for? Swimming pools are huge, by volume, and heating that much water takes a massive amount of heat energy...and there is just no cheap way to accomplish this. If you start to research the cheapest way to heat your pool there is a definitive answer that you can find however you might overlook it due to the simplicity of the solution.
Cover Your Pool - The simple solution to expensive pool heat is to simply need to heat your pool less. Way less. Using a pool cover on your pool very night can reduce the amount of heat energy that your pool loses by as much as 90%. When you really start to look at the cost of pool heating, natural gas, propane and electricity costs, the number one important thing you must do is conserve the heat that you have already paid for. Paying to heat your pool but letting that heat simply escape into the atmosphere at night is the best way to increase the cost of heating your pool. If you want to reduce your costs as much as possible then put a solar blanket over your pool every night (and be sure to remove it during the day to prevent algae growth).
Pool Heater Buying Guide
If you found this page but scrolled right to the bottom because this is simply too much information for you to read and absorb then you can consider this pool heater buying guide quick reference section. What you need to know in order to make the best choice for a new pool heater is that:
1) Gas heaters are better for any time heat, where electric heat pumps are best for improving in-season swimming temperatures in warm climate areas.
2) If your gas heater is not installed correctly it will almost certainly fail early. Be sure that your heater has a water bypass installed, the heater is bonded, and there is a check valve preventing any chlorine injection systems from tracing back into the heater.
3) When sizing your pool heater you are far better off to get one a little too big as opposed to a little too small. While there are many different sizes and models of pool heaters on the market, by far the most common sizes are around 250k BTU and 400k BTU and most likely you will end up choosing one of these two sizes.
4) Learn to balance your water properly to avoid early heater failure. One of the worst water chemistry situations for a pool heater is high chlorine levels combined with low pH levels so be sure to avoid this. You should also have your heater cleaned yearly to make sure it maintains the correct air-to-fuel burn ratio to maintain its efficiency rating.
5) Pool heat is expensive regardless of which type or size of heater that you have. The best possible thing that you can do as pool owner to reduce your heating costs and increase you swimming temperature is to use a solar blanket on the pool every night.
If you skipped the rest of the very important information on this page but still managed to follow the five simple steps outlined above then you probably will end up with a heater that you are happy with. The vast majority of unhappy pool heater owners are ones that have had a heater fail early due to poor installation or water chemistry issues but they incorrectly blame the heater manufacturer as being the source of the problem. If you want the best pool heater then follow these five steps, and then select one of the heaters that were rated "the best" in this pool heater comparison article where gas technicians and pool heater experts explained which brands and models of pool heater they like working with the best: What is the best pool heater?
How to choose the right size pool heater
What would make a pool heater fail early?
The new heater buying checklist
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If you need to order swimming pool equipment, parts or chemicals online then you should choose to buy from a specialist that deals exclusively with pool and spa products. InTheSwim.com would be my recommendation to pool owners looking to shop online for pool and spa supplies.
- Swimming Pool Steve
I can not stress enough the importance of using a waterproofing solution for concrete swimming pools. When it comes to the technical process of waterproofing concrete pools Basecrete is the most effective product that I know of. I strongly endorse the use of Basecrete products to all concrete pool owners.
- Swimming Pool Steve
Pool installations can be very expensive especially when you start to add optional extras. Building a pool is a once in a lifetime event for most people and it is important to get the pool you want. Swimming pool financing can help you get the pool you want and make sure you have the money you need to do it right the first time.
- Swimming Pool Steve
When it comes to ordering pool and spa supplies online in Canada www.PoolSuppliesCanada.ca is by far the best option. They carry everything from chemicals to replacement pumps to entire pool kits, with free shipping options and more "in stock" items than any other Canadian online retailer.
- Swimming Pool Steve